* {
    scroll-behavior: smooth;
}

.container {
    .fly-to-top {
        position: fixed;
        bottom: 100px;
        right: 20px;
        transform: translateY(0);
        width: 143px;
        height: 85px;
        background: url(src/assets/space-to-top.png);
        background-position: 0px -44px;
        z-index: 999;
        &:hover {
            animation:back 0.5s steps(7) infinite
        }
    }
    #fly-to-top-id {
        display: none;
    }
    //动画
    @keyframes back {
        from {
            background-position: 1000px -44px;
        }
        to {
            background-position: 0px -44px;
        }
    }
}